# 添加删除vps中的swap分区
**URL:** https://eijil.com/t/vps-swap/41
**Category:** 其它
**Created:** [December 31, 2020, 10:04am UTC](https://eijil.com/t/vps-swap/41 "2020-12-31T10:04:56Z")
**Posts on this page:** 5
**Page:** 1
### Author:  [@linuxren](https://eijil.com/u/linuxren)
#### Post date: [December 31, 2020, 10:04am UTC](https://eijil.com/t/vps-swap/41/1 "2020-12-31T10:04:56Z")
大部分vps都没有swap分区，下面的办法提供了增加一个2G swap分区的方式
**创建分区**
fallocate -l 2G /swapfile
chmod 600 /swapfile
mkswap /swapfile
swapon /swapfile
echo “/swapfile swap swap defaults 0 0” \>\> /etc/fstab
**删除分区**
swapoff -v /swapfile
---
### Author:  [@Tristan](https://eijil.com/u/Tristan)
#### Post date: [November 12, 2024, 3:48am UTC](https://eijil.com/t/vps-swap/41/2 "2024-11-12T03:48:01Z")
首先，创建swap的基本步骤是:
### 创建swap文件:
```auto
sudo fallocate -l 4G /swapfile
# 或者用 dd 命令替代
sudo dd if=/dev/zero of=/swapfile bs=1G count=4
```
- fallocate 更快但部分文件系统可能不支持
- dd 命令更通用，bs是块大小，count是块数量
### 设置权限:
```auto
sudo chmod 600 /swapfile
```
- 出于安全考虑，只允许root读写
### 格式化为swap:
```auto
sudo mkswap /swapfile
```
- 将文件标记为swap格式
### 启用swap:
```auto
sudo swapon /swapfile
```
- 激活swap分区
### 设置开机自动挂载:
```auto
echo '/swapfile none swap sw 0 0' | sudo tee -a /etc/fstab
```
- 将配置写入fstab文件
### 这些命令中:
- 1-4是必须的
- 第5步是可选的，但建议添加以实现开机自动挂载
---
### Author:  [@Tristan](https://eijil.com/u/Tristan)
#### Post date: [November 12, 2024, 3:49am UTC](https://eijil.com/t/vps-swap/41/3 "2024-11-12T03:49:23Z")
删除swap:
### 首先停用swap:
```auto
sudo swapoff /swapfile
```
- 这会让系统停止使用该swap
- 系统会将swap中的数据移回内存
### 从fstab中删除自动挂载项:
```auto
sudo vim /etc/fstab
```
### 找到并删除这一行:
```auto
/swapfile none swap sw 0 0
```
或者用sed命令:
```auto
sudo sed -i '/swapfile/d' /etc/fstab
```
### 删除swap文件:
```auto
sudo rm /swapfile
```
确认swap已被删除:
```auto
# 查看当前swap使用情况
free -h
# 或者
swapon --show
```
---
### Author:  [@Tristan](https://eijil.com/u/Tristan)
#### Post date: [November 12, 2024, 3:52am UTC](https://eijil.com/t/vps-swap/41/4 "2024-11-12T03:52:32Z")
@Chatbot Translate this thread to English please!
---
### Author:  [@Chatbot](https://eijil.com/u/Chatbot)
#### Post date: [November 12, 2024, 3:52am UTC](https://eijil.com/t/vps-swap/41/5 "2024-11-12T03:52:46Z")
Certainly! Here’s the translation of the thread:
* * *
**linuxren said:** Most VPS do not have a swap partition. The following method provides a way to add a 2GB swap partition.
**Creating the partition:**
```bash
fallocate -l 2G /swapfile
chmod 600 /swapfile
mkswap /swapfile
swapon /swapfile
echo "/swapfile swap swap defaults 0 0" >> /etc/fstab
```
**Deleting the partition:**
```bash
swapoff -v /swapfile
```
* * *
**Tristan said:** First, the basic steps to create a swap file are:
### Create a swap file:
```bash
sudo fallocate -l 4G /swapfile
# Or use the dd command as an alternative
sudo dd if=/dev/zero of=/swapfile bs=1G count=4
```
- `fallocate` is faster but may not be supported by some file systems.
- `dd` is more universal; `bs` is block size, and `count` is the number of blocks.
### Set permissions:
```bash
sudo chmod 600 /swapfile
```
- For security reasons, only root is allowed to read and write.
### Format as swap:
```bash
sudo mkswap /swapfile
```
- This marks the file as swap format.
### Enable swap:
```bash
sudo swapon /swapfile
```
- This activates the swap partition.
### Set to auto-mount at boot:
```bash
echo '/swapfile none swap sw 0 0' | sudo tee -a /etc/fstab
```
- This writes the configuration to the fstab file.
### These commands:
- Steps 1-4 are mandatory.
- Step 5 is optional but recommended to ensure auto-mount at boot.
* * *
**Tristan said:** To delete swap:
### First, disable swap:
```bash
sudo swapoff /swapfile
```
- This will stop the system from using the swap.
- The system will move data from the swap back to memory.
### Remove the auto-mount entry from fstab:
```bash
sudo vim /etc/fstab
```
### Find and delete this line:
```bash
/swapfile none swap sw 0 0
```
Or use the sed command:
```bash
sudo sed -i '/swapfile/d' /etc/fstab
```
### Delete the swap file:
```bash
sudo rm /swapfile
```
Confirm that the swap has been deleted:
```bash
# Check current swap usage
free -h
# Or
swapon --show
```
* * *
Let me know if you need anything else!